I just got my 2005, IP, 6MT Coupe yesterday. Very impressed with the car, I got Nav., Premium Pkg, Spoiler, 19" Forged Wheels and Stone Interior. The Navigation if by far my favorite thing so far.
I had a 2003 350z, but traded it a year ago and got a Titan. I've been missing it ever since. My initial impression is the G35 is quick, but the weight difference between the 350z and the G35 is evident. But in all fairness my 350z had Intake, Plenum, Nismo Exhaust, & Test Pipes on it so that may be part of the difference.
I can't wait to start the Mod process all over again..

Congrats, 350_Z, and welcome to 'Driver.
You would expect that the Z may be slightly quicker due to the weight diff.

Have fun with that Navi, it's one on my faves too.

C.